The US Food and Drug Administration (FDA) has granted accelerated approval to polatuzumab vedotin-piiq (Polivy, Genentech/Roche), in combination with the chemotherapy bendamustine and rituximab (BR), to treat adults with previously treated diffuse large B-cell lymphoma (DLBCL).
The approval, which is restricted to patients who have relapsed or are treatment refractory (r/r) after at least two prior therapies, was granted based on complete response rates observed in a randomized controlled clinical trial.
Polatuzumab is a first-in-class antibody-drug conjugate. The new drug binds to a specific protein (CD79b) found only on B cells, then releases chemotherapy into those cells.
"Antibody-drug conjugates are an emerging class of targeted immunotherapies for cancer. This type of therapy, unlike traditional chemotherapy, is intended to target specific cells," said Richard Pazdur, MD, director of the FDA's Oncology Center of Excellence and acting director of the Office of Hematology and Oncology Products, Center for Drug Evaluation and Research.
DLBCL is the most common type of non-Hodgkin lymphoma and is curable. However, about 30% to 40% of patients relapse.
"Today's approval of [polatuzumab] provides an alternative option for patients in whom multiple treatments have not worked," said Pazdur.
The accelerated approval was based on the results from the phase 1b/2 GO29365 study among 80 patients with relapsed or refractory DLBCL who were randomly assigned to receive polatuzumab with BR (n = 40) or BR alone (n = 40). The patients were not candidates for hematopoietic stem cell transplant at study entry.
Enrolled patients had received a median of two prior therapies.
The complete response rate at the end of treatment, which was the primary endpoint, was 40% with polatuzumab plus BR compared with 18% with BR alone.
Of the 25 patients treated with polatuzumab plus BR who achieved a complete or partial response, 16 (64%) had a duration of response lasting at least 6 months as compared with 3 (30%) of the 10 people treated with BR alone. Additionally, 12 (48%) of the 25 patients treated with polatuzumab plus BR had a duration of response lasting at least 1 year as compared with 2 (20%) of 10 people treated with BR alone.
The most common side effects of polatuzumab plus BR include neutropenia, thrombocytopenia, and anemia; peripheral neuropathy; fatigue; diarrhea; fever; decreased appetite; and pneumonia, according to the FDA.
The FDA advises that healthcare professionals monitor patients closely for infusion-related reactions, low blood counts, and fatal and/or serious infections. Also, patients should be monitored for tumor lysis syndrome, hepatotoxicity, and progressive multifocal leukoencephalopathy, said the agency.
Cite this: FDA Approves First Chemoimmunotherapy for R/R Lymphoma Type - Medscape - Jun 10, 2019.